Entry 1 sense Webster, 1913 Iconoclasm /īkˌ-än'-ək-lăzˌ-əm/ · I·con·o·clasm · IPA /aɪˈkɒnəˌklæzəm/ 01 n. The doctrine or practice of the iconoclasts; image breaking. 1. The doctrine or practice of the iconoclasts; image breaking.